1. Field of the Invention
This invention relates to systems for enabling the measurement and marking of distances and angles.
2. Description of the Prior Art
Rigid folding rulers have been known for some time. Such rulers include the folding ruler disclosed in U.S. Pat. No. 7,111,408, filed on Feb. 2, 2005 to James M. Critelli et al., and U.S. Patent Pub. No. 2003/000096A1, published on Jan. 2, 2003 to Chien-Kuo Wang. The entire contents of both references are herein incorporated by reference.